How to make bitmaps for graphic LCD (glcd)?

Making bitmaps for graphic LCD is pretty easy. There is a lot of free tools available over Internet, but I think there is no need to download them if you have already installed an image editing software in your PC. Also it is interesting to know what's actually they do. In this quick tutorial,  an example using GIMP - a free image manipulation program is described. This is a general tutorial and can be applicable for almost all type of graphical LCDs.

Step1: Know the pixel size of your graphic LCD. For KS0108 (a general purpose glcd), it is 128x64.
Step2: Choose an image(any image) to be embedded on LCD.
Step3: Scale the image to 128x64. In GIMP, (menu)Image -> Scale Image. Change height to 64 and width to 128.
If your image is not an exact multiple of 128x64 and if you want to keep the aspect ratio, you need to do any of the following:
a) Crop the image to 128x64.From toolBox(dock in the left hand side most probably), choose Rectangle Select Tool and spcify the size to 128x64 in the bottom of toolbox and select a portion you want and crop it. (menu)Image -> Crop to Selection.
b) Resize the image to less than or equal to 128x64. Then start a new image by (menu)File -> New. Then from the dialog box choose size as 128x64. Copy the previous image to the new image.
c) If you want to just check and image is not matter, image search on Google specifying the size 128x64 ;-)
Step4: Before going to this step, I assume you have an image of the same size of your LCD. In this example, 128x64. Next is the conversion of your color image to monochrome image. For that, choose, (menu)Colors -> Threshold. Using the dialog box, you can change the threshold in realtime.
Step5: Change mode.(menu)Image -> Mode -> Indexed.From the dialog box, choose 'Use Black and White (1bit) palette'. Click 'Convert'
Step6: Save the image.(menu)File -> Save as. Choose extension .bmp (bitmap).

Now your image is ready for embedding to your LCD. For some programs like MikroC for PIC, there is a built in tool to convert the bitmap into array. If you don't have such advanced tools, don't worry, let's do it using open source tools.
Using Octave/Matlab for KS0108
Now you have a monochrome bitmap of only zeros and ones. Now it should be grouped and formatted to a format supported by glcd. I did the conversion using octave. The script shown below accepts the bitmap name as argument and convert it to the glcd compatible form. make appropriate changes to run the script in MATLAB. Also change yourself the program if your lcd size is different.

#This code input a monochrome bitmap of size 128x64 and convert it to a form compatible to ks0108 graphic lcd(glcd)
arg_list=argv();
x=imread(arg_list{1}); #accept argument
num=0;
printf("Controller 1 (left)\n\n");
page=0;
for offset = [1:8:64]
    printf("Page %d:\n",page);
    page+=1;
    for j=1:64
        for i=[offset:offset+7]
            num=num+x(i,j)*(2^(i-offset));
        endfor
        printf("%d ",255-num);
        num=0;
    endfor
    printf("\n\n");
endfor
printf("Controller 2 (right)\n\n");
page=0;
for offset = [1:8:64]
    printf("Page %d:\n",page);
    page+=1;
    for j=65:128
        for i=[offset:offset+7]
            num=num+x(i,j)*(2^(i-offset));
        endfor
        printf("%d ",255-num);
        num=0;
    endfor
    printf("\n\n");
endfor